Lifting jack



June 10, 1930. A, HOPKINS 1,762,627

LIFTING JACK Filed April 24, 1926 2 Sheets-Sheet 1 4 {Q [N VEN TOR A TTO/(NE YS' June 10, 1930. c, HOPKINS 1,762,627

LIFTING JACK Filed April 24, 1926 2 Sheets-Sheet 2 INVENTOR A 715mm KS Patented June 10, 1930 Wires Mei-3,527

f ARTHUR C. HOPKINS, OF NILES, MICHIGAN, Ti.) NATIGNAL STANDARD GOM- PANY, OF NILE-1S, MICFIGAN LIFTING JACK Application filed April 2 My present invention relates to improvements in lifting jacks of the type shown in LettersPatent No. 1,559,098 granted me October 27, 1925.

The main object of this invention is to provide an improved actuating means which 1s easily manipulated and has a large amount of power.

A further object is to provide an improved actuating means which can be quickly and easily reversed or adjusted for raising or lowering the load.

Objects pertaining to details and economics of construction and operation of my improvements will definitely appear from the detailed description to follow. The invention is clearly defined and pointed out in the claims.

A structure embodying the features of my invention is clearly illustrated in the accompanying drawing forming a part of this application, in which:

Fig. 1 isa side view of my improved jack, the actuating lever being partially broken away.

Fig. 2 is a fragmentary longitudinal vertical section on a line corresponding to line 22 of Figs. 1 and 5, the lifting lever being in'its lowered position.

Fig. 3 is a view similar tothat of Fig. 2 with the parts in another position, the lifting lever being partially raised.

Fig. at is a fragmentary plan view.

Fig. 5 is a transverse section on lines 55 of Figs. 1, 2 and 4.

Fig. (i is a fragmentary section showing the reversing member in operative position for lowering the lifting lever, the actuating lever being at the limit of its down stroke, in which position the holding pawl is disengaged.

Fig. 7 is a view similar to that of Fig. 6 with the actuating lever at the limit of its up stroke in which position the holding pawl is engaged and the lifting pawl released.

Serial No. 104,361.

Referring to the drawing, the frame of my improved jack comprises spaced side members 1, 1 connected at their forward ends by the axle 2 provided with wheels 3. The rear ends of the frame side members are provided with feet 4. The frame is further connected by a cross rod 5.

A lifting lever 6 is mounted on the pivot rod 7 extending between the side members, the lifting lever being provided with a ratchet segment 8 having its axial center in the pivot- 7 for the lever. The head member 9 is pivoted at 10 on the end of the lifting lever and provided with stepped work engaging rests 11 and 12.

This head member is maintained in its upright position by means of the link 13 which is pivoted at 14 on the rod 5 and is pivotally connected to the head member at 15, the link being arranged in parallel relation to the lever 6 So that as the lever is swung up and down in raising andloivering the rod the head member is maintained in upright position.

The actuating lever 16 is bifurcated, its arms 17 being mounted on the rod 18 which also constitutes a frame cross member. The actuating lever has arms 19 which project downwardly below the pivot and carry the lifting pawl 20 mounted on the pivot 21' carried by these arms 19. A holding pawl 22 is mounted on the actuating lever pivot 18.

Springs 2-3 and 2d are mounted on the pivot members 21 and 18, respectively, and arranged to yieldingly urge the pawls to engaging position. With the parts thus arranged the oscillating of the actuating, lever wirl raise the lifting lever, the pawls ratcheting along the face of the ratchet segment 8.

To reverse the movement and lower the jack I provide the lifting pawl with a finger-like tripping member 25 preferably in the form of a leaf spring, which is mounted on the pawl to project upwardly and rearwardly from its pivot. A leverlike tripping member 26 is pivoted at 27 on a pin projecting from one of the frame members at the side of the segment 8 and projects rearwardly above the pivot 13. This member 26 has a downwardly offset agar end 28 terminating in a cam shoulder A reversing member 30 having a cross piece 31 at its lower end is slidably mounted on the handle in the embodiment illustrated, the arms of the handle being longitudinally slotted at 32 to slidably support the reversing member. When the reversing member is in its retracted position shown in Figs. 2 and 3 it clears the tripping members as the actuating lever is oscillated. hen the reversing member is movedto its operative position as shown in Figs. 6 and 7 it alternately engages the tripping member 25 and the tripping member 28, actuating them to alternately throw out the pawls.

The tripping member 28 carries a spring member 33 thus permitting a yielding of the tripping means until the load is sufficiently released therefrom to permit them to disengage and to insure further that one of them shall always be in engaging position.

The reversing member is further supported and manipulated by means of the shifting rod 34 sliding through a point 35 at the inner end of the actuating lever and is held in its adjusted positions by means of a handpiece 36 which is pivotally mounted on the rod to be adjusted into different engaging. positions with the keeper 37. This provides a positive means for securing the reversing member in its operative or inoperative position, and also provides for the convenient manipulation thereof from the outer end of the actuating lever.

' Stops 38 and 39 are positioned on the actuating lever to engage with the frame and limit the stroke of the actuating lever.

My improved lifting jack is simple and economical in its parts, the parts may be readily assembled, and are arranged so that they are very durable. The structure also has the advantage of being very easily manipulated for raising or lowering the load.

Having thus described my invention what I claim as new and desire to secure by Letters Patent:

1. In a lifting jack, the combination of a frame comprising spaced side members, a lifting lever pivotally mounted between said side members and provided with a ratchet segment, a head member pivotally mounted on said lifting lever, a head sup porting link pivotally connected to said frame and to said head member in parallel relation to said lifting lever for maintaining said head member in upright position, a bifurcated actuating lever having longitudinal slots in the arms thereof, a pivot therefor extending between said side members, a lifting pawl disposed between said lever arms and pivotally mounted thereon to coact with said ratchet segment, a hold-. ing pawl pivotally mounted on the actuating lever pivot between its arms to coact with said segment, springs acting to urge said pawis to engaging position, a tripping lever pivotally mounted on one of said frame side members at the side of said segment to project rearwardly and having a downwardly offset rear end provided with a cam shoulder, said tripping. lever being provided with a spring finger engaging said holding pawl, a spring tripping member mounted on said lifting pawl to' project rearwardly and upwardly from its pivot, and a reversing member slidably mounted in said slots in said actuating lever arms to be shifted forwardly into position to coact alternately with said holding pawl tripping lever and said actuating pawl tripping member when the actuating lever is oscillated.

2. In a lifting jack, the combination of a frame comprising spaced side members, a lifting lever provided with a pivoted ratchet segment, a bifurcated actuating lever having longitudinal slots in the arms thereof, a pivot therefor extending between said side mem ers, a lifting pawl disposed between said lever arms and pivotally mounted thereon to coact with said ratchet segment, a hold g pawl pivotally mountedon the actuatin W lever pivot between its arms to coact with said segment, springs acting to urge said pawls to engaging position, a trip ing lever pivotally mounted on one of said frame side members at the side of said segment to project rearwardly and having a downwardly offset rear end provided with a cam shoulder, said tripping lever being provided with a spring finger engaging said holding pawl, a spring tripping .member mounted on said lifting pawl to pro ect rearwardly and upwardly from its pivot, a reversing member slidably mounted in said slots in said actuating lever arms to be shifted forwardly into position to coact alternately with said holding pawl tripping lever and said actuating pawl tripping ineniher when the actuating lever is oscillated, and a shifting rod on which said reversing I member is mounted slidably on said actuat-- ing lever. 4 I

3. In a lifting jack, the combination of a frame comprising spaced side members, a lifting lever provided with a pivoted ratchet segment, a bifurcated actuating lever having longitudinal slots in the arms thereof, a pivot therefor extending be 'ween said side members, a lifting pawl disposed between said lever arms and pivotally mounted thereon'to coact with said ratchet segment, a holding pawl pivotally mounted on the actuating lever pivot between its arms to coact with said segment, springs acting to urge said pawls to engaging position, a tripping lever pivotally mounted on one of said frame side members at the side of said segment to project rearwardly and having a downwardly offset rear end provided with a cam shoulder, said tripping lever being provided with a spring finger engaging said holding pawl, a spring tripping member mounted on said lifting pawl to project rearwardly and upwardly from its pivot, and a reversing member slidably mounted in said slots in said actuating lever arms to be shifted forwardly into position to coact alternately with said holding pawl tripping lever and said actuating pawl tripping member when the actuating lever is oscillated.

4:. In a lifting jack, the combination of a frame, a lifting lever pivotally mounted on said frame and provided with a ratchet segment, a head member pivotally mounted on said lifting lever, a head supporting link pivotally connected to said frame and to said head member in parallel relation to said lifting lever for maintaining said head member in upright position, an actuating lever pivotally mounted on said frame, a lifting pawl pivotally mounted on said lever to coact with said ratchet segment, a pivotally mounted holding pawl, springs acting to urge said pawls to engaging position, a trippin lever pivotally mounted on said frame and having a downwardly off-- set rear end provided with a cam shoulder, said tripping lever being provided with a spring finger engaging said holding pawl, a spring tripping member mounted on said lifting pawl to project rearwardly from its pivot, and a reversing member slidably mounted on said actuating lever to be shifted forwardly into position to coact alternately with said holding pawl tripping lever and said actuating pawl tripping member when the actuating lever is oscillated.

5. In a lifting jack, the combination of a frame, a lifting lever pivotally mounted on said frame and provided with a ratchet segment, an actuating lever pivotally mounted on said frame, a lifting pawl pivotally mounted on said lever to coact with said ratchet segment, a pivotally mounted holding pawl, springs acting to urge said pawls to engaging position, a tripping lever pivotally mounted on said frame and having a downwardly offset rear end provided with a cam shoulder, said tripping lever being provided with a spring finger engaging said holding pawl, a spring tripping member mounted on said lifting pawl to project rearwardly from its pivot, and a reversing member slidably mounted on said actuating lever to be shifted forwardly into position to coact alternately with said holding pawl tripping lever and said actuating pawl tripping member when the actuating lever is oscillated.

6. In a lifting jack, the combination of a frame, a lifting lever pivotally mounted on raid frame and provided with a segment, a holding pawl coacting with said segment, a pivoted actuating lever, a tripping member pivotally mounted on said frame and having a yielding engagement with said holding pawl, said tripping member being disposed above said holding pawl and having a downwardly offset rear end, a lifting pawl pivotally mounted on said actuating lever and provided with an inclined upwardly projecting tripping member, a reversing member adjustably mounted on said actuating lever to alternately coact with said tripping members, and an adjusting rod therefor slidably mounted on said actuating lever and provided with a pivoted handpiece, said lever being provided with a keeper with which said handpiece may be adjustably engaged for supporting said reversing member in operative or inoperative position.

7. In a lifting jack, the combination of a frame, a lifting lever pivotally mounted on said frame and provided with a segment, a holding pawl coacting with said segment, a pivoted actuating lever, a tripping member pivotally mounted on said frame and having a yielding engagement with said holding pawl, said tripping member being disposed above said holding pawl and having a downwardly offset rear end, a lifting pawl pivotally mounted on said actuating lever and provided with an inclined upwardly projecting tripping member, a reversing member adjustably mounted on said actuating lever to alternately coact with said tripping members, and an adjusting rod therefor slidably mounted on said actuating lever.

8. In a lifting jack, the combination of a frame, a lifting member mounted on said frame and provided with an actuating segment, a holding pawl coacting with said segment, a pivoted actuating lever, a trip ping member pivotally mounted on said frame and having a yieldin engagement with said holding pawl, said tripping member being disposed above said holding pawl and having a downwardly offset rear end, a lifting pawl pivotally mounted on said actuating lever to coact with said segment and provided with an inclined upwardly projecting tripping member, and a reversing member slidably mounted on said actuating lever to alternately coact with said tripping members as the actuating lever is oscillated. v

9. In a lifting jack, the combination of a frame, a lifting lever mounted on said frame and provided with an actuating se ment, an actuating lever pivotally mounted on said frame, a lifting pawl carried by said actuating lever, a holding pawl, springs acting to urge said pawls to engaging position, a pivotally mounted tripping member provided with a spring finger coacting with said holding pawl, a rearwardly projecting spring tripping member on said lifting pawl, and a reversing member adjustably mounted on said actuating lever to be shifted to and from operative position in which position it alternately coacts with said tripping lever and said tripping finger.

10. In a lifting jack, the combination of a frame, a lifting lever mounted on said frame and provided with an actuating seg ment, an actuating lever pivotally mounted on said frame, a lifting pawl carried by said actuating lever, a holding pawl, springs acting to urge said pawls to engaging position, a pivotally mounted tripping member coacting with said holding pawl, a rearwardly projecting tripping member on said lifting pawl, and a reversing member adjustably mounted on said actuating lever to be shifted to and from operative position in which 0- sition it alternately coacts with said tripping lever and said tripping member on said lifting pawl.

11. I11 a lifting jack, the combination of a frame, a lifting member provided with an actuating segment, a pivoted holding pawl coacting with said segment, an actuating lever pivotally mounted on said frame, a lifting pawl mounted on said actuating lever and provided with a spring tripping member projecting upwardly at the rear of the lever pivot, a pivotally mounted holding pawl tripping member operatively associated with said holding pawl and provided with a part projecting rearwardly of said actuating lever pivot, and a reversing member adjustably mounted on said actuating lever to alternately coact with said tripping members.

12. In a lifting jack, the combination of a frame, a lifting member provided with an actuating segment, a pivoted holding pawl coacting with said segment, an actuating lever pivotally mounted on said frame, a lifting pawl mounted on said actuating lever and provided with a tripping member projecting at the rear of the lever pivot, a holding pawl tripping member operatively associated with said holding pawl and projecting rearwardly of said actuating lever pivot in crossed relation to said actuating paw tripping member, and a reversing member adjustably mounted on said actuating lever to alternately coact with said tripping members.

13. In a lifting jack, the combination of a frame, a lifting member provided with an actuating segment, a pivoted holding pawl my hand.

ARTHUR C. HOPKINS. 

